Audi 2.4 Fuse 5 Blows

[AUDIDolley]

In need of your help, where do I start fuse 5 always blows, need your advise urgently.
Thanks,
Wayne

[s1turbomike]

Does the manual tell you what fuse 5 does???
This will help you in diagnosing the fault.
If you dont know what the fuse does check everything you can, to see what is not working in the car!

[AUDIDolley]

Been fault finding and can now confirm that with the climate panel removed the fuse does not blow, I have even gone as far to now confirm that the fuse only blows when the 'D' connector is plugged into the climate panel. Now what I dont know is this an input or an output therefore still not 100% sure it is this panel that is defected, can anyone advise?

Many thanks,


Wayne

[s1turbomike]

Try taking the the climate control panel and check to see if there is any signs of corroded parts or if the pcb has any burnt tracks.

[AUDIDolley]

I have removed the PCB and am struggling to see any signs of damage.

Thanks, Wayne

[s1turbomike]

Hi Wayne
It's sounds like you have found your fault in the climate pack. The only other thing I would check is the speed resistor behind the glove box for the fan speed and the motor. Disconnect both of those and then reconnect the climate pack and if fuse blows then go for a new display. Does the fuse state that it powers any thing else!!

[AUDIDolley]

Could you kindly tell me where to locate and what size the speed resistor is, if the reisistor had burnt out, surely it would not cause the fuse to blow?

Thanks,
Wayne

[s1turbomike]

To locate the speed resistor and fan you need to remove the glovebox as it is all behind it.From memory some resistor packs are red. The speed resistor is normally bolted on the side of the heater ducts to help keep the resistor cool. It should have a plug with a few wires attached. Has the dash been removed at any stage and does it have an aftermarket stereo or hands free kit? These could have been tapped into vehicle wiring behind stereo!
Sorry to bombard you with all these questions, it just gives me a better chance to help solve this problem.:D

[AUDIDolley]

Dash does not appear to have been removed, std stereo and no sign of hands free kit.
What I can confirm is that with socket D disconnected from the climate panel with fuse 5 in place the fuse does not blow and with the ignition on the fans run fast, the climate panel remains dead with no functioning.

Based on this do you still see the speed resistor could be a possible cause, what type of DC motor is used, ie if the speed resistor had blown surely the climate panel would work but with no speed control. I am blowing a 10amp fuse so I something has to be shorted to earth.

Let me have your feedback, the mornings are getting colder.
Cheers


Wayne

[s1turbomike]

you say the fans are still running fast. This is a good thing as when speed resistors fails they only run on full speed. I would definatly check that now. Diconnect it and put a new fuse in. Hopefully it wont blow the fuse. The fan is the only other componant which could blow that fuse without melting the insulation on the wires
Please check both regardless as the fan could be damaging the resistor (ie dry bearings putting strain on the resistor).
The speed resistor drops its voltage in line with the speed control on the display. The lower the speed the greater resistance is needed so when it packs up the only function available is full speed as its not resisted.

I hope this helps before the cold weather sets in fully.

[AUDIDolley]

OK I will but can the speed resistor give me a dead short and hence blow this fuse if it was faulty?

I assumed that if it was faulty everything would operate I would just not have any speed control of the fan.

What do you think?

Wayne

[s1turbomike]

Your right to a degree. But don't cast it aside as this can give a dead short as it is a circuit with a live and earth.

[AUDIDolley]

Well guys afurther update.

I have pulled all the spades out of the connector and can now confirm that the fuse blows when only red/black and two brown wires are connected so this only three wires connected in the 16 pin housing the other removed and insulated for the sake of fault finding.

Pins 9, 14 and 15 connected.

Firstly any ideas what 14 and 15 are? 9 is the supply from the fuse.

Please can someone give me further advice should I take a seperate 12v supply to pin 9?
Could the actual control panel be taking down a 10amp fuse how can I verify this either way.

Many thanks

Wayne

[s1turbomike]

Brown in the diagram shows that they are both earth wires so it seems to be inside the climate pack which has allowed the power supply to short out against an earth . Looks like you need a new climate pack.

[AUDIDolley]

I think you are right, does anyone know if these climate panels are repairable or does anyone have a second hand one they could sell me.

Many thanks,

Wayne

[AUDIDolley]

I have identified that there is a blown diode surface mounted on the PCB. Can anyone repair this for me for a price?
Thanks,
Wayne

[s1turbomike]

I can give it a go if you like for the price of a diode and postage. Labour free. If that helps you out.